1. Field of the Invention
The present invention relates to a plasma display device, and more particularly to a plasma display device that efficiently dissipates heat from a driver IC packaged in a format of a tape carrier package (hereinafter, referred to as “TCP”).
2. Description of the Related Art
A plasma display device is an apparatus that displays an image on a plasma display panel (PDP) using plasma generated by a gas discharge. The plasma display device includes the PDP, a chassis base supporting the PDP, and a plurality of printed circuit board assemblies (PBAs). The PBAs are disposed at a side of the chassis base opposite to that of the PDP. The PBAs are electrically connected to display electrodes and address electrodes disposed within the PDP.
In the plasma display device, an electrode printed on the PDP is generally electrically connected to a PBA through a flexible printed circuit (hereinafter, referred to as “FPC”). In other words, a discharge cell in the PDP is addressed by the address electrode and the display electrode provided within the PDP. A sustain discharge subsequently occurs in the addressed discharge cell to realize the image. In order to achieve these, the electrodes provided within the PDP lead out through the FPC and are connected to the PBAs and are thus controlled by the PBAs.
The address electrode is connected to a PBA through a tape carrier package (TCP) that packages the driver IC. An address pulse is applied to the address electrode through the driver IC. In other words, in order to selectively form a wall voltage in a pixel of the PDP, the driver IC repeatedly applies an address pulse to a corresponding address electrode within a short period of time depending on a control signal received from a driving circuit.
As a structure for applying voltage using the FPC and the driver IC, a chip on board (COB), a chip on film (COF), or the TCP type can be used. The COB has a structure for mounting the driver IC on a printed circuit board (PCB), and the COF has a structure for directly mounting the driver IC on a film constituting the FPC. Recently, the TCP, having a small size and a low price, has been used.
The TCP has the following construction. First, a bump of the driver IC is bonded and attached to a pattern. The bump is formed of gold (Au). The pattern is formed of copper (Cu) and is disposed on an insulating film generally formed of polyimide. After that, resin is coated on the bump and the pattern to protect the combination of the bump and the pattern. A pattern protective layer (solder resist) is used to insulate the pattern. The pattern includes a power source, a signal input wire, and a ground wire.
With such an arrangement, the driver IC packaged in the format of a TCP generates an address discharge at least eight times during 1/60 second corresponding to one TV field, in order to express 256 or more grayscales in the PDP. When the PDP is driven, high temperatures and electromagnetic interference (EMI) occurs.
In order to dissipate heat from the driver IC, a heat dissipation sheet, which is formed of a solid material and serves as a heat sink, is attached to the TCP to dissipate heat generated by the driver IC into the atmosphere. However, this arrangement has a drawback in that a large amount of heat produced by the driver IC cannot be endured due to its inability to rapidly dissipate the produced heat. As a result, the driver IC is destroyed. What is needed is a more effective heat dissipation mechanism for such an IC driver located on a TCP.